Obviously, the princess would be one of the main characters. There might also be a charming prince or a dashing knight as the male lead. And there could be a scheming villain, perhaps an envious noble or a power - hungry courtier.
One interesting aspect could be its setting. It might be set in a grand, fictional kingdom which adds a touch of magic and allure. The characters in 'la princesa' are likely to be complex and well - developed, with the princess herself having a unique personality.
In terms of the plot, it could start with Sombra's return or some sort of threat that he poses. Luna then steps in to deal with it. The setting within the My Little Pony world would be important. It could be set in Canterlot or some other location. The fanfic might also introduce new characters or use existing ones to support the main plotline between Luna and Sombra.
One popular story could be about the characters going on an epic adventure within the Smosh Games universe. Maybe they have to overcome various challenges and puzzles in a virtual world. It might involve teamwork and some comical moments as well.
One common theme could be the battle between light and dark. Luna represents the moon and has an association with the night, which can be seen as a time of mystery and sometimes danger. King Sombra is a dark character. So the fanfic may explore this contrast in terms of their powers and personalities.
First, you should familiarize yourself with the Smosh Games world and the Joven character. Watch a lot of their videos to get a sense of their personalities and the kind of scenarios they are usually in. Then, come up with an interesting concept or plot. It could be something as simple as Joven getting lost in a new game level.
Since I don't know the exact story, it could potentially be about a figure who met a watery end and was considered beautiful in a way that defies normal expectations. It could be a story about love and loss, where the person who drowned was remembered in a special way that made them seem the most beautiful. It might also be a story with a moral or lesson, perhaps about the transience of life and the power of memory.